Electrical switch.



J L. ADAMS, JR. ELECTRICAL SWITCH.

APPLICATION FILED NOV. 16. 191 1.

Patented Nov. 30, 1915.

2 SHEETSSHEET 1.

ATTORNEY J L. ADAMS, JR. ELECTRICAL SWITCH.

APPLICATION FILED NOV. 16. 191i.

wi zwm.

AiTORNEY UNITED STATES PATENT OFFICE.

JAMES L. ADAMS, JR., OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR 'lO WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

ELECTRICAL SWITCH.

Specification of Letters Patent.

Patented Nov. 30, 1915.

To all whom it may concern Be it known that I, JAMES L, ADAMS, Jr., a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electrical Switches, of which the following is a specification.

My invention relates to centrifugally actuated switches for use in connection with electrical generators and motors to automatically establish and interrupt the circuits of such machines when they operate at predetermined speeds.

The object of my invention is to provide a centrifugally actuated switch of the character and for the purpose indicated which shall be simple and compact in construction and effective and reliable in operation.

My invention is illustrated in the accompanying drawings, Figure 1 of which is a view in end elevation of a small generator embodying the same, certain of the parts thereof being broken away for the sake of clearness of illustration. Fig. 2 is a vertical axial sectional view of the generator shown in Fig. 1. Fig. 3 is a plan view of the switch and the actuating means therefor. Fig. 4 is a development of the centrifugally actuated arm of the switch-actuating means, and F 5 is a side view of the positionaccentuating means for the switch.

The invention maybe conveniently, and is here shown as, employed in connection with a small generator that is adapted to generate current for automobile ignition and lighting purposes, the generator comprising a stationary field frame 1 and an armature 2 that is mounted upon a shaft 3, for which suitable bearings 4c are provided in an end bracket 5 with which the field,

frame is provided.

Mounted upon the shaft 3 and near one end thereof, and also closely adjacent to the armature proper, is a spider 6 of irregular shape having a main portion 7 of cylindrically curved outer contour and a slotted lug 8 in which a centrifugally actuated and cylindrically curved lever 9 is pivotally secured. One arm of the lever 9 is longer than the other and the free end of its shorter arm is inclined with respect to both its side and circumferential faces to form a cam 9. The longer arm of the lever 9 is provided with an intermediate slightly raised or stepped portion 10 having acam face 10 which is also inclined with respect to both its side circumferential faces but is directed oppositely to the cam 9 at the end of the shorter arm of the lever and is laterally displaced somewhat with respect thereto. The lever 9 is normally maintained in the posit1on shown by means of a helical tension spring 11 that is stretched between the longer arm of the lever and the main portion 7 of the spider, the cam 9 at the end of the shorter arm of the lever having its greatest radius of movement under this condition. The longer arm of the lever is Weighted so that, when the armature rotates at greater than a predetermined speed, the said arm is moved outwardly by centrifugal force against the tension of the spring, thereby moving the cam 10 outwardly and the cam 9 inwardly. The two extreme positions of the lever 9 are accentuated by means of a spring 12 that is" carried by the spider 6, and the free end of which bears upon a V-shaped lug 9 upon lever 9.

The cams upon the lever 9 are adapted to actuate a switch member in the one direction or the other, according to their positions, the said member being here shown as comprising a reversely bent spring 13, the extremity of the shorter leg of which is pivotally secured to the end bracket 5 at 13*, and the extremity of the longer leg of which is provided with a roller 14 that engages a track 15 having recesses 15 and 15 to accentuate the positions of the switch member. Attached to the shorter leg-of the spring 13, adjacent to its pivotal point, is an arm 16 carrying a conducting button 17 that is adapted to engage a pair of separated contact terminals 18 that are connected to a binding ost 19 on the end bracket 5. The 7 other end of the arm 16 bears upon and resiliently presses forward a pin 20 that projects through, and is loosely secured in, the h reversely bent end of the spring 13 so as to be capable of longitudinal movement with respect thereto. The pin 20 is provided with a conical head 20 that projects into the outer paths of movement of the cams 9 and 10 and is moved thereby to the one side or the other, according to which cam is outermost, carrying with it the whole switch member. When the armature of the machine is at rest, the position of the switch member is such that the button 17 does not engage the contact terminals 18 and the circuit of the generator is open. As the machine attains a predetermined speed, the longer arm of the lever 9 is thrown outwardly by centrifugal force, carrying with it the cam 10 which is brought into engagement with the pin 20 during rotation of the armature The pin is thus moved to one side to cause the button 17 to engage the contact terminals 18 and thereby close the circuit of the generator. When the speed of the armature diminishes below a predetermined value, the spring 11 draws the longer end of the lever 9 inwardly and throws the shorter end thereof out- Wardly to engage the pin 20 on the switch member and actuate the switch to open the circuit of the generator. It will be understood that the parts 14: and 15 accentuate the positions of the switch member and that, after it has been moved in the one direction or the other, it will remain in the position to which it has been moved, and the pin carried thereby will not be again engaged by 'since the circuit between the generator and the battery is not established until the generator speed and voltage have attained predetermined values. However, other uses may, of course, be made of the switch, though, by reason of its compactness and simplicity of construction, it is particularly useful in the connection shown.

It will be noted that, by reason of the inclination of the engaging surfaces of the cams carried by the centrifugally actuated lever and the pin carried by the switch member, the said parts lock together when once brought into engagement and remain locked together until the lateral movement of the pin and switch member are completed. Also, by reason of the fact that the direction of movement of the centrifugally actuated lever is transverse to the direction of movement of the switch member, the rotative force of the armature is employed for actuating the switch member rather than the centrifugal force exerted upon the lever, which is the result of the rotation thereof. Consequently, the force required for the operation of the switch member does not oppose centrifugal force, and the operation of the switch is accordingly eifective, reliable and sensitive to changes of speed.

I claim as my invention:

1. The combination with a rotatable member, and a lever pivotally mounted thereon and having oppositely directed cams upon opposite sides of its pivotal point, of a switch member interposed in the path of, and actuated by, the one or the other of the said cams, according to the speed of the r0- tatable member.

2. The combination with a rotatable member, and a lever pivotally mounted thereon and having cams upon opposite sides of its pivotal point, of a switch member interposed in the path of, and actuated by, the one or the other of the said cams, according to the speed of the rotatable member.

3. The combination with a rotatable memher, and a centrifugally actuated lever carried by said member and having two cams, of a switch having a movable member that is adapted to occupy either an open circuit or a closed-circuit position and is moved to the respective positions by the same cams, in accordance with the speed of the rotatable member.

4:. The combination with a rotatable member, and a centrifugally actuated lever pivotally mounted upon said member and having oppositely directed cams upon opposite I sides of its pivotal point, of a switch member interposed in the path of, and actuated by, the one or the other of the said cams, according to the speed of the rotatable member, the engaging faces of the cams and switch member being inclined.

5. The combination with a rotatable member, and a centrifugally actuated lever pivotally mounted upon said member and having cams upon opposite sides of its pivotal point, of a suitable member interposed in the path of, and actuated by, the one or the other of the said cams, according to the speed of the rotatable member, the engaging faces of the cams and switch member being inclined.

6. The combination with a rotatable member, and a substantially cylindrical centrifugally actuated lever pivotally mounted upon said member and having oppositely directed cams upon its outer cylindrical face and upon opposite sides of its pivotal point, of a switch member interposed in the path of,

and actuated by, the one or the other of said ber being inclined.

8. The combinationwith a rotatable member, and a substantially cylindrical centrifugally actuated lever pivotally mounted upon said member and having oppositely directed cams upon its. outer cylindrical face and upon opposite sides. of its pivotal point, of a switch member interposed in the path of, and actuated by, theone or the other of said cams, according to the speed of the rotatable member.

9. The combination with a rotatable member, and a substantially cylindrical centrifugally actuated lever having oppositely directed cams upon its outer cylindrical face and upon opposite sides of its pivotal point, of a switch member that is movable transversely to the plane of rotation of the rotatable member and is interposed in the path of, and actuated by, the one or the other of said cams, according to the speed of the rotatable member, the engaging faces of the cams and switch member being inclined.

10. The combination with a rotatable member provided With two centrifugally displaced cam surfaces, of a switch member that is moved to two definite positions by said surfaces in accordance with two predetermined speeds of said rotatable member.

In testimony whereof, I have hereunto subscribed my name this 13th day of Nov.

JAMES L. ADAMS, JR. Witnesses:

A. W. COPLEY, B. B. HINES. 

